Pivoted bender and resilient backup plate for folding edge of wire screen



Nov. 19, 1957 A. LANG 2,813,570

PIVOTED BENDER AND RESILIENT BACK-UP PLATE FOR FOLDING EDGE OF .WIRE SCREEN Filed Jan. 4. 1954 2 Sheets-Sheet 1 I INVENTOR. ALBEPI LA/ V6 k 7' TOP/W345 Nov'. 19, 1957 A. LANG PIVOTED BENDER AND RESILIENT BACK-UP PLATE FOR FOLDING EDGE OF WIRE SCREEN 2 Sheets-Sheet 2 Filed Jan. 4. 1954 as ,14 37 as. as

INVENTOR. ALBA-W7 m/va hired States Patent PIVOTED BENDER AND RESILIENT BACK- g PIEATE FOR FOLDING EDGE OF WIRE RE N Albert Lang, Oakland, Calif., assignor t Rudiger-Lang (10., Berkeley, Calif., a corporation of California Application January 4, 1954, Serial No. 401,937

3 Claims. (Cl. 153-20) In the process of manufacturing tension type window screens it is necessary to form a reverse fold of uniform width along one or more edges of the wire cloth. This operation is normally accomplished with a bending device known as a bending brake.

It is the principal object of this invention to provide an improved bending brake for making a reverse fold of uniform width along an edge of a piece of wire cloth.

A further object of this invention is to provide an improved bending brake for making a reverse fold of uniform width along one edge of a piece of wire cloth which may be attached to the side edge of a work table.

A still further object is to provide an improved bend ing brake for making a reverse fold of uniform width along one edge of a piece of wire cloth which is simple to operate, and both simple and economical to produce.

Various other objects of the invention will be apparent from the following description taken in connection with the accompanying drawings, wherein:

Fig. 1 is a perspective view of a device embodying the principles of my invention, and showing the manner in which the device is fastened to the side edge of the table.

Fig. 2 is a sectional view taken on line 22 of Fig. l, and showing the device with the parts in the position which they will occupy when the edge of a piece of wire cloth is inserted ready for the bending operation.

Fig. 3 is a view similar to that shown in Fig. 2, showing the parts in an intermediate position during the bending operation.

Fig. 4 is a view similar to Fig. 2, showing the parts in the position they will occupy at the end of the bending operation.

Fig. 5 is a view similar to Fig. 2, showing the use of the device for crimping the fold after the bending operation has been completed.

Fig. 6 is a sectional view, similar to Fig. 2, of a modified form of the invention.

Referring now to the drawings, wherein similar reference numerals are used to designate similar elements through the various views shown, reference numeral 10 indicates a work table upon which the wire cloth is adapted to be stretched.

The bending brake comprises an L-shaped angle member 11 having a horizontal flange 12 adapted to be connected to the lower surface of the table top 10, said member 12 projecting outwardly therefrom, and a vertical flange 13 extending downwardly from the outer end of the horizontal flange 12. The horizontal flange 12 is fastened to the undersurface of the table top by a plurality of machine screws 14 threaded into openings provided in said flange. The machine screws are countersunk into the table top so that their upper surfaces are coincident with the upper surface of the table.

One leaf 15 of a hinge-like assembly is interposed be tween the upper surface of the flange 12 and the under surface of the table top 10, and is held in place by the machine screws 14 previously mentioned. The outer 2,813,570 Patented N av. 19,. 1957 'ice end of the leaf 15 is turned up around and holds a hinge pin 16 parallel and adjacent to the edge of the table top 10. A second leaf member 17, having a flat upper surface, is hinged to the hinge pin 16 and extends laterally outward from the table top 10. The inner end of leaf 17 is approximately in the same plane as the plane of the table top. A torsion spring 18 is wrapped around the hinge pin 16 and has one of its ends bearing on the under surface of the leaf 17, the other end bearing on the upper surface of the flange 12, whereby the leaf 17 is urged away from the flange 12 and extends outwardly and slightly upward, from the surface of the table top 10. A stop lug 19, formed integral with the leaf 17, is adapted to bear against the upper surface of the flange 12 and to limit the upward movement of the leaf.

One leaf 20 of a second hinge-like assembly is connected to the outer surface of the vertical flange 13 by a plurality of bolts 21 held in place by a plurality of nuts 22. The upper end of the leaf 20 is curved around and holds a hinge pin 23 adjacent the outer end of the leaf 17, when said leaf is in its uppermost position. A second leaf 24 is pivotally connected to the hinge pin 23 and extends generally laterally outward therefrom.

A second L-shaped member 25 has one flange 26 resting on the upper surface of the leaf 24 with the inner end thereof spaced slightly from the hinge pin 23. A bending plate, or blade 28 rests on the upper surface of the flange 26 and has its inner end extending beyond the inner end of said flange 26. The leaf 24, the flange 26 and the plate 28 are held together by a plurality of flat-head machine bolts 29 countersunk so that the upper surfaces of the bolts are coincident with the surface of the plate 28, said bolts being held in place by a plurality of nuts 30. It can be seen that the end of the flange 26 forms an abutment against which the end of the wire cloth 33 abuts, when it is inserted in the space between the leaf 24 and bending plate 28. The free end of plate 28 will describe an arc concentric with the axis of hinge pin 23 as the plate 28 is moved around the hinge pin 23.

The other flange 27 of the L-shaped member 25 extends generally downwardly from the outer end of the flange 26. An adjustable stop screw 31 is threaded into an opening provided in flange 26 and is locked in its adjusted position by a lock nut 32. The stop screw 31 is adapted to abut against the leaf 20 and limit the piv otal movement of the L-shaped member 25 to a position wherein the groove formed between the leaf 24 and the bending plate 28 will be facing and generally parallel to the surface of the leaf 17.

In the modification shown in Fig. 6, the second L-.

shaped member 25 and the parts associated therewith are the same as those shown and described with respect to Figs. 2 through 5. However, in place of the hinged leaf 17, a fixed plate 36 is fastened to the flange 12 with a spacer block 35 therebetween to locate the upper surface of the plate 36 in the same plane as the: upper surface of the table top 10. A spacer 34 is provided between the undersurface of the table top 10 and the flange 12 to locate the main supporting L-shaped member 11 in such a position that the upper end of the leaf 20 supporting the hinge 23 will be in the same plane as the table top 10. The inner end of the plate 36 is bent downwardly to form a flange 37 which is adapted to abut against the edge of the table top 10. The outer end portion 38 of the plate 36 is bent downwardly approximately at an angle of 45 and terminates just short of abutment with the flange 12. The end portion 38 of plate 36 intersects the are described by the .rotation of bending plate 28, so that when the bending member is pivoted around the hinge pin 23 and the inner end of the plate 28 contacts the portion 38 of the plate 36, the plate will spring downwardly to provide clearance be- 3. tween the surface 38 of the plate 36 and the surface of the plate 28 for the main body of the wire cloth 33 as the edge portion thereof is bent around the edge of the plate 28 in=the manner illustrated in Fig. 4-.

In operation of the device, the wire cloth is placed on the, table and slidlaterally toward the bending brake attached to the edgeof the table so that one edge thereof enters into the groove formedbetween the leaf 24 and the bending plate 28 and abuts the inner end of the flange 26 in the manner shown in Fig. 2. The bending assembly is then pivoted around the hinge pin 23 in the manner shown in. Fig. 3 until it reaches the position shown in Fig. 4, wherein the edge portion of the screen will be bent back upon itself. The bending mechanism is. then pivoted outwardly, at which time the plate 28 will swing out. from inside of the folded portion of the screen, leaving the edge .of the screen folded. The folded portion of the screen is then inserted between the surfaces of the leaf 17 and plate 28 and crimped in the manner shown in Fig- 5. If a double fold is desired, the folded edge may thenbe inserted in the groove and the operation. repeated.

While I have shown and described thepreferred form of myinvention, it is to be understood that various changes may be made in its construction by those skilled in the art without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a screen bending brake adapted to be secured adjacent one edge of a work table, a bending means pivotally mounted at one end on an axis parallel to and spaced outwardly from said table edge and rotatable about said axis from a first to a second position, a bending blade carried by said end of said bending means and having an edge parallel to and spaced from said axis, whereby rotation of said bending means will cause the bending blade edge to describe an arc concentric with said axis, a groove in said end of said bending means parallel to and between said bending blade and said axis and having an open end adapted to face said tablev edge when said bending means is in its first position, a resilient back-up plate adapted to have one edge thereof secured adjacent said table edge, said back-up plate extending towards said bending means and normally intersecting said are, whereby when said bending means is rotated from its first to its second position said bending blade edge will engage said back-up plate to force it out of intersection with said arc, the back-up plate returning towards its normal position and in engagement with said bending blade after said bending blade passes thereby to its second position, and an upper surface portion on said back-up plate coplanar with said groove when said bending means is in its first position.

2. In a screen bending brake adapted to be secured adjacent one edge of a work table, a bending means pivotally mounted at one end on an axis parallel to and spaced outwardly from said table edge and rotatable about said axis from a first to a second position, a bending blade carried by said end of said. bending means and having an edge parallel to and spaced from said axis, whereby rotation of said bending means will cause the bending blade edge to describe an arc concentric with said axis, a groove in said end of said bending means parallel to and between said bending blade, and said axis and having an open end adapted to face said table edge when said bending means is in its first position, a resilient back-up plate adapted to have one edge thereof pivotally mounted adjacent said table edge for rotation about an axis parallel to said bending means axis, saidback-up plate having a portion thereof extending towards said bending means, and spring means normally biasing said back-up plate into intersection with said arc, whereby when said bending means is rotated from its first to its second position, said bending blade edge will engage said back-up plate to force it against said spring bias out of intersection with said arc, the back-,upplate being biased back towards its normal position and in engagement with said bending blade after said bending blade edge passes thereby to its second position, said back-up plate having an upper surface portion thereof coplanar with said groove when said bending means is inits' first position.

3. In a screen bendingbrake adapted to be secured adjacent one edge of a work table, a bending means pivotally mounted atone end on an axis parallel to and spaced outwardly from said table edge and rotatable about said axis from a first to a second position, a bending blade carried by said end of said bending means and having an edge parallel to and spaced from said axis, whereby rotation of said bending means will cause the bending blade edge to describe an arc concentric with said axis, a groove in said end of said bending means parallel to and between said bending blade and said axis and having an open end adapted to face said table edge when said bending means is in its first position, a resilient back-up plate having a portion thereof adapted to be fixedly supported adjacent said table edge and a resilient unsupported portion which extends downwardly and outwardly from said fixed portion into normal intersection with said arc, Whereby when said bending means is rotated from its first to its second position said bending blade edge will engage said back-up plate to force it downwardly out of intersection with said arc, the back-up plate springing back upwardly against said bending plate after said bending blade edge passes thereby to its second position, and an upper surface portion on said back-up plate coplanar with said groove when said bending means is in its first position.

References Cited in the file of this patent UNITED STATES PATENTS 305,757 Phillips Sept. 30, 1884 480,396 Clark Aug. 9, 1892 594,643 Mehrman Nov. 30, 1897 670,504 Danzer Mar. 26, 1901 713,062 Cobb Nov. 11, 1902 1,267,368 Bowles May 28, 1918 2,255,368 Smith Sept. 9, 1941 2,436,278 Willett Feb. 17, 1948 FOREIGN PATENTS 1,878 Great Britain Feb. 7, 1887 44,090 Germany Aug. 1, 1888 

